- print_r: documentation ( source)
<?php
$master = array();
$arrColors = array('R', 'B', 'G' ,'Y');
$arrNumbers = array('1', '2', '3', '4');
foreach($arrColors as $color) {
foreach($arrNumbers as $num) {
$master += array($color => $num);
//echo $color.' => '.$num;
//echo "\n";
}
$master += $master;
}
print_r($master);